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Effect of Epoxy-Based Structural Foam on Energy Management: An Experimental & Analytical Investigation
ISSN: 0148-7191, e-ISSN: 2688-3627
Published March 05, 2001 by SAE International in United States
Annotation ability available
Event: SAE 2001 World Congress
The effect of epoxy-based structural foam on strength, stiffness, and energy absorption of foam filled structural components is investigated and implemented to formulate design guide-lines that can be used in enhancing weight reduction and engineering functions of systems.
An experimental approach is first utilized to identify design variables such as foam density, gage, and foam layer thickness, that are needed to enhance the weight/ performance ratio of structural hat-section components. A CAE approach using non-linear, large deformation finite element analysis is used to model the hat-section components. An acceptance level of confidence in the CAE analytical tools is then established based on comparisons of results between the two approaches. Upon that, the CAE analytical tools are deployed in a sensitivity study to quantify the crush/crash characteristics of foam-filled hat-section components with respect to the changes in the afore mentioned design variables. Design charts are presented, from which design variables can be selected for particular applications in order to establish the weight effectiveness of foam reinforcement.
In the foam thickness range investigated (5–8 mm), the axially absorbed energy increased between 50–125%, while the maximum axial strength increased by 10–25% only. On the other hand, the flexural energy absorption increased from 10–40%, while the maximum bending load registered an increase ranging from 25 to 80%. Therefore, the use of thin gages accompanied by foam layers in the 5 to 8 mm range would result in the most efficient energy absorbing axial structural components. In addition, maximum bending strength can also be increased with almost no weight penalty, by deploying similar thicknesses of the epoxy-based foam in beam components. The cut-off gages for the efficiency of the epoxy-based foam (in the studied foam thickness layers of 5–8 mm) ranges from 1.4-1.8 mm for flexural applications and from 2.0–2.2mm for axial applications.
The enhancement in the structural characteristics of columns and beams through structural foam deployment, is due to a delayed local buckling mechanism. On the other hand, foam deployment in beams has to be enhanced in density and location, where plastic hinges are likely to form. This enhancement in location will minimize the total weight of the component thus maximizing the total specific energy gain per that member.
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CitationAlwan, J., Wu, C., and Chou, C., "Effect of Epoxy-Based Structural Foam on Energy Management: An Experimental & Analytical Investigation," SAE Technical Paper 2001-01-0473, 2001, https://doi.org/10.4271/2001-01-0473.
SAE 2001 Transactions Journal of Passenger Cars - Mechanical Systems
Number: V110-6; Published: 2002-09-15
Number: V110-6; Published: 2002-09-15
- March 30 1993
- Bores, A. P. Sidebottom, O. M. “Advanced Mechanics of Materials” 3rd Edition 1978 John Wiley and Sons New York 670
- Mahmood, H. F. Paluszny, A. “Design of Thin Wall Columns for Crash Energy Management-Their Strength and Mode of Collapse” Transactions SAE, 90, 4039 1981
- Abed, S. H. Doane, R. M. “An Analytical Approach To Predict Maximum Bending Strength of Thin-Walled Beams Composed of High and Mild Strength Steel” May 1993
- Lampinen, B. E. Jeryan, R. A. “Effectiveness of Polyurethane Foam in Energy Absorbing Structures” May 1982
- Thornton, P. H. “Energy Absorption by Foam Filled Structures” SAE Technical Paper Series, Congress and Exposition Feb. 1980
- Montgomery, D. C. Analysis of Experiments New York John Wiley and Sons 1991
- Walpole, R. E. Raymond, H. M. Probability and Statistics for Engineers and Scientists 4th Edition New York Macmillan Publishing Company 1989
- Lilley, K. Mani, A. “Roof-Crush Strength Improvement Using Rigid Polyurethane Foam” SAE, Topics in Vehicle Safety Technology, SP-1139 Feb. 1996 35 45
- Chou, C. C. Zhao, Y. Lim, G. G. Patel, R. Shahab, S. Patel, P. “Comparative Analysis of Different Energy Absorbing Materials for Interior Head Impact” SAE paper No. 950332 1995
- Bilkhu, B. B. Founas, M. Nusholtz, G. S. Du Bois, P. “Techniques fo Numerical Modelling of Cellular Materials using Material Models #5, #10, #41 in LS-DYNA3D” The Second International LS-DYNA3D Conference held in San Francisco September 20–21 1994
- Chang, F.S. Hallquist, J. O. Lu, D.X. Shahidi, B.K. Kudelko, C. M. Tekelly, J. P. “Finite Element Analysis of Low-Density High-Hysteresis Foam Materials and the Application in the Automotive Industry” SAE Paper 940908 1994
- Alwan, J Wu, C.C. Chou, Clifford “ Effect of Polyurthane Foam on The Energy Management of Structural Components” SAE 2000-01-0052 Feb. 2000